Sanding control means



Feb. 25, 1941. I E, wn- 2,232,915

SANDING CONTROL MEANS Filed Dec. 30, 1939 ELLIS E.HEW IT 1' BY We, {M

ATTORNEY :mssusu I SEP 30 1941 Patented Feb. 25 1941 SANDING ooNraoLMEANS Ellis E. Hewitt, Edgewood, Pa., assignor to The Westinghouse AirBrake Company, Wilmerding, Pa., a corporation of PennsylvaniaApplication December 30, 1939, Serial No. 311,920 17 Claims. (01. 291'3) This invention .relates to sanding, apparatus and more particularlyto the type for use on railwayvehicles for sanding track rails.

Inthe modern high speed railway trains greater and faster acting brakingforces are required on the vehicle wheels than heretofore employed inorder to decelerate or stop the trains in the relatively shortdistancesnecessary to meet operating schedules and to insure the safetyof the trains. In order to minimize slipping or sliding of the wheelswhen the brakes are thus applied sand is usually applied to the rails toincrease the friction between the wheels and rails.

Sanding arrangements heretofore used on railway trains have been sodesigned as to provide a substantially uniform rate of flow of sand forsanding the rails. The same amount of sand has thus been provided forsanding the rails when the train is operating at high speed as whenoperating at lower speeds. It has therefore been necessary to designthese arrangements to insure an adequate amount of sand on the rails forthe maximum speed of the train' with the obvious result that :anexcessive amount of sand is applied to the rails at'all lower speeds.This naturally results in the wasting of sand at the lower speeds andhas required larger amounts of sand being carried on trains than wouldhave otherwise been required.

One object of the present invention is to provide an improved sandingarrangement for railway vehicles or trains adapted to minimize waste ofsand such as just described, but which will insure an adequate supply ofsand to the track rails at all train speeds to provide most efficientbraking of the train under all conditions.

Another ob'ject of the invention is to provide an improved sandingapparatus for use on railway vehicles or trains which is so arranged asto provide an amount of sand for sanding purposes which variessubstantially according to the speed at which the train or vehicle isoperating.

The present invention is. particularly adapted for use on railwayvehicles provided with brakeequipment of the type controlled by aspeedgovernor device which operates in accordance with the speed of thevehicle to provide different degrees of braking effort for differentranges of speed in order to minimize the possibility of slipdevice, suchas just described, to provide different amounts of sand for sanding thetrack rail for the different speed ranges of the train or vehicle, thatis, to provide a relatively large amount of sand for sanding when thetrain or vehicle is operating in a relatively high speed range, andproportionately less amounts of sand for sanding when operating in lowerspeed ranges.

Other objects and advantages will be apparent from the following moredetailed description of the invention.

In the accompanying drawing, the singlefigure is :a diagrammatic View;partly in section and partly in outline, of a combined fluid pressurebrake equipment and improved sanding arrangement constructed inaccordance with the invention. v

Description -As shown in the drawing, the fluid pressure brake equipmentemployed for illustrating one application of the invention comprises anengineers brake valve device I, a fluid pressure controlledbrake'controlling valve device 2, a differential; relay' valve device 3,a speed governor device I I, a fluid pressure suply control valve devicel2, and a manually operative self-opening electric switch [3 which isdisposed adjacent the brake valve device I for operation by theengineer.

- The engineers brake valve device I is preferably of the combinedautomatic and self-lapping straight air type disclosed in Patent2,106,483 issued to me on January25, '1938, and comprises a casing M towhich there are connected a brake pipe l5, a straight air pipe [6 and afluid pressure supply pipe H. The pipe I! is connected tothe feed valvedevice 1 which is adapted to operate in the usual manner to supply fluidat a desired reduced pressure to said pipe from the main reservoir 6whichmay be supplied with fluid .under pressure in any desired manner.

On one side of easing Hi there is provided a selector handle l8 which ismovable to either one or another of two positions for selecting whetherthe brakes of the vehicle will be controlled auto- }matically throughthe brake pipe I5 or by straight air through the straight air pipe IS. Ahandle I9 is provided for the engineer to operate the brake valve deviceto control the brakes on'the vehicle in accordance with the position ofthe selector handle IS.

The brake controlling valve device 2 may be of any desired type which isadapted to operate upon a reduction in pressure in brake pipe |5 toeffect an application of brakes on the vehicle and. upon an increase insaid pressure to effect a releaseof brakes on the vehicle. However, forthe purpose of illustration, it is shown as of the type disclosed inPatent 2,152,257 issued to me and Donald L. McNeal on March 28, 1939,but only those parts are shown which are required to illustrate thepresent invention.

As shown, the brake controlling valve device 2 comprises a pipe braket20 to one face of which is connected the brake pipe I5, fluid pressuresupply pipe l1, straight air pipe l6 and a brake application and releasepipe 2| leading to the differential relay valve device 3 and pneumaticswitch device 5.

On another face of the pipe bracket 20 there is mounted a serviceapplication portion 22, only a portion of which is shown, and which isadapted to operate upon a service reduction in pressure in brake pipe I5to supply fluid under pressure to a passage 23 for effecting a serviceapplication of the brakes on the vehicle and which is adapted to operateupon an increase in pressure in the brake pipe to release fluid underpressure from said passage to effect a release of the brakes.

On another face of pipe bracket 20 there is mounted an emergency valveportion 24 which is adapted to operate together with the serviceapplication portion 22 upon an emergency reduction in brake pipepressure to supply fluid under pressure to passage 23 for-effecting anemergency application of the brakes on the vehicle.

Associated with the emergency valve device 24 is a brake pipe vent valvedevice comprising a vent valve 25 for controlling an emergencycommunication between a passage 26, and thereby the brake pipe l5 towhich said passage is connected, and an atmospheric vent 21 throughwhich, when said valve is open, an emergency venting of fluid underpressure from the brake pipe is adapted to be effected in the usualmanner. The vent valve device further comprises a piston 28 connected bya stem 29a to the vent valve 25 and which is adapted to be operated byfluid under pressure supplied to a chamber 29 at one side of said pistonfor opening said vent valve against the pressure of a spring 30. Thefluid under pressure for operating the vent valve piston 28 is adaptedto be obtained from the emergency valve device 24 upon the usualemergency operation thereof and such pressure is adapted to bedissipated through .a choke 3| provided in said piston and connectingchamber 29 to the vent passage 21. The spring 30 is provided for closingthe vent valve 25.

Preferabl associated with the pipe bracket 20 of the brake controllingvalve device is a, double check valve device 32 comprising .a doublecheck valve 33 which is arranged to operate in the usual manner tocontrol communication between the brake application and release pipe 2|and a passage 34 connected to the straight air pipe I6 on the one hand,and the passage 23 through which the brakes on the vehicle are adaptedto be controlled by automatic operation of the brake controlling valvedevice 2 on the other hand.

Briefly, the operation of the brake valve device I and brake controllingvalve device 2 is as follows.

When the selector handle IS on the engineers brake valve device I is inthe straight air position and the brake valve handle I9 is operated toeffect .a straight air application of the brakes, fluid under pressureis adapted to be supplied to the straight air pipe Hi from which it willflow by passage 34 to one end of the double check valve 33 and shiftsaid check valve to the position shown in the drawing. With the checkvalve 33 in this position fluid under pressure supplied to passage 34 isadapted to flow to the application and release pipe 2| for effecting astraight air application of brakes on the vehicle as will hereinafter bemore fully described. Upon subsequent operation of the brake valvedevice I to effect a release of the brakes, fluid under pressure will bevented from the brake application and release pipe 2| by way of thestraight air pipe I6, as will be apparent.

If it is desired that the brakes on the vehicle be controlledautomatically, the selector handle I8 is turned to the automaticposition. When the brake valve handle I9 is then operated to effect .anapplication of the brakes on the vehicle the pressure in brake pipe I5is reduced. The brake controlling valve device 2 then operates inaccordance with whether the reduction in brake pipe pressure is at aservice rate or an emergency rate to supply fluid under pressure to theautomatic application passage 23 of the pipe bracket 20. This supply offluid under pressure to passage 23 is adapted to shift the double checkvalve 33 from the position shown to its left-hand position to closecommunication between pipe 2| and the straight air pipe passage 34.Fluid supplied to passage 23 is then adapted to flow to pipe 2| forapplying the brakes on the vehicle.

When the brake controlling valve device 2 operates upon an emergencyreduction in brake pipe pressure as just described, it is also adaptedto supply fluid under pressure to the vent valve piston chamber '29 foroperating piston 4 5 28 to unseat the vent valve 25 so as to locallyvent fluid under pressure from the brake pipe l5 to the atmospherethrough the vent port 21 at an emergency rate for propagating theemergency reduction in brake pipe pressure to the next car in the train,in the usual well known manner. Also, as well known, the supply of fluidunder pressure to piston chamber 29 for operating the piston 28 tounseat the vent valve 25 is limited and will be gradually dissipated tothe atmosphere through vent port 36 in said piston. The capacity of thisvent port is however so related to the amount of fluid pressure supplyas to maintain the vent valve 25 unseated sufiiciently long to insuresubstantially complete venting of fluid from the brake pipe at whichtime the spring 3|) is adapted to act to seat the vent valve 25.

When the brake valve handle I9 is operated to effect an increase inpressure in the brake pipe l5, for releasing the brakes on the vehicle,subsequent to either a service or emergency application of brakes, thebrake controlling valve device will respond and operate to release fluidunder pressure from the automatic application and release passage 23 andthereby from the brake application and release pipe 2|.

Thus'it will be evident that regardless of whether the brakes on thevehicle are controlled by straight air through the straight air pipe IEor automatically by operation of the brake controlling valve device 2,such control is efl-ected by way of the application and release pipe 2|.

A further description of the construction and operation of the brakevalve device I and brake controlling valve device 2 is notdeemedessential to a comprehensive understanding of the inyention.

The differential relayvalvedevice'3 employed to illustrate a use of theinvention may be similar to that disclosed in Patent 2,140,624 issued tome on December 20, 1938, and which is adapted to operate upon the supplyof fiuid under pressure to the application and release pipe 2| to supplyfluid to the brake cylinder device 8 and to vary the pressure obtainedinsaid brake cylinder device in accordance with the speed at which thevehicle is operating as governed by the speed governor device 4. p

The differential relay valve device comprises a self-lapping applicationand release valve portion 35, a diaphragm portion 36 and a magnetportion 31.

The self-lapping application and release valve portion 35, the detailsof which are not shown in the drawing, is adapted to operate inaccordance with the degree of force applied thereto by the diaphragmportion 36 to supply fluid under pressure fromthe supply pipe I! to thebrake cylinder device 8 and to release fluid under pressure from saiddevice as required to maintain the pressure in said brake cylinderdevice in proportion to the degree of said force.

The diaphragm portion 36 comprises four flexible diaphragms 38, 39, 40and. 4| which are 00- axially arranged in spaced relation andoperatively connected to the application and release valve portion 35.These diaphragms are of different efiective areas stepped down in sizein the order named. An operating chamber 42 is provided between thediaphragms 38 and 39, an operating chamber 43 is provided between thediaphragms 39 and 40, an operating chamber 44 is provided between thediaphragms 46 and 4|, while at the outer face of the smallest diaphragm4| there is provided a chamber 45 which is in permanent communicationwith the application and release pipe 2|, by way of passages '46, 4'!and 48.

The magnet portion 31 of the relay valve device comprises a high speedelectro-magnet valve device 50, a medium speed electro-magnet valvedevice 5| and a lowspeed electr c-magnet valve device 52.

The high speed electro-hiagnet valve device 50 comprises a magnet 53 anda pair of oppositely seating valves 54 and 55; said magnet beingoperative upon energization to seat the valve 54 and to unseat the valve55 for opening communication between the application and the releasepipe passage 48 and a passage 56 which leads to diaphragm chamber 42 Aspring 51 is provided to act, upon deenergization of magnet 53 to seatvalve 55 and to unseat valve 54 for connecting passage 56 with anatmospheric vent passage 58. v i

The medium speed electro-magnet valve device 5| comprises a magnet 59ama pair of oppositely seating valves 6|] and 6|. This magnet isoperativeupon energization to seat thevalve 6|] and to unseat valve 6| forsupplying fluid under pressure from the application and release pipepassage 48 to a passage 62 leading to diaphragm chamber 43. A spring 63is provided to seat valve 6| and to unseat valve 66 upon deenergizationThe speed governor device comprises a centrifuge 'HJ adapted to berotated from and at a speed proportional to that of any suitable part ofa vehicle, such as an axle or wheel (not shown). A vertically movableshaft II is provided for control by centrifuge l0 and is adapted to bemoved thereby to various vertical positions, dependent upon the speed atwhich the vehicle is operating.

The shaft H carries three movable contact fingers I2, 13 and 14 forengagement respectively with three sets of fixed contact fingers I5, 16and 11. The movable contact 12 is fixed for movement with the shaft IThe contacts I3 and 14 are slidably mounted on the shaft 14 at eitherside of a collar 69 fixed to said shaft and between said collar and eachof said contacts there is disposed a spring 16a. A collar 69a is fixedon the shaft 1| at the opposite side of and for engaging the contact I3to move same out ofengagement with the fingers 16 upon downward movementof shaft 1|, while a collar 18 is fixed on said shaft below the contactI4 for engaging same to lift it out of contact withfingers 11 uponmovement of shaft H in an upwardly direction.

All of the parts just described are so arranged that above a certainhigh speed limit of the vehicle the contacts 12 and 13 will electricallyconnect fingers 15 and 16, respectively, as shown in the drawing. Theshaft H is adapted to move downwardly upon a reduction in vehicle speedand to move the contact 12 out of engagement with the fingers 15 at thetime the speed of the vehicle reduces below the high speed limit, justmentioned. The contact 13 is adapted to maintain engagement with thefingers 16 until the shaft 1| obtains a position corresponding to amedium speed limit of the vehicle. downward movement of the shaft 14 isthen adapted to pull the contact 13 out of engagement with the finger16. When the shaft H obtains a still lower position, corresponding to ofthe governor contacts 14, I3 and 12 will be just the reverse of thatobtained upon a reduction in vehicle speed, as will be apparent.

The stationary contact fingers 15, I6 and 11 at one side of the shaft Hare all connected to a common wire 80, while-at the other side of saidshaft the fingers are connected respectively to the high speed magnet53, the medium speed magnet 59 and the low speed magnet 65.

The pneumatic switch device 5 comprises a casing containing a piston 8|having at one side a chamber 82-connected to the application and releasepipe 2|, while at the opposite side of said piston there is provided aspring 83 for urging said piston in the direction of said chamber. The

piston 8| is provided with a stem 84 on the 011 8 Further end of which acontact 89 is arranged for movement into circuit closing relation with apair of fixed contacts 86 one of which is connected to the wire 99 whilethe other is connected to one terminal of a battery 91 the otherterminal of which is grounded.

The rail sanders 9 may be of any conventional type from which sand isadapted to be blown by fluid under pressure to an outlet for supply tothe track rails; one sander 9 being provided for each of the rails undera vehicle. As'shown in the drawing, each of the rail sanders 9 comprisesa casing 99 having at one end adjacent the top thereof a sand inletconnection with a sand box 9| from which sand is adapted to flow bygravity into the sander. At the opposite end of the casing and adjacentthe bottom thereof there is provided an outlet to a pipe 92 throughwhich sand is adapted to be conveyed by gravity to the track rail.

A cleaning pipe 93 and a pipe 94 are connected to the casing 99 of eachof the rail sanders, it being noted that said sanders are shown in thedrawing connected in parallel. The cleaning pipe 93 is provided forconveying fluid under pressure directly into the sanders for cleaningsame while the pipe 94 is provided for conveying fluid under pressure tothe sanders for blowing sand, supplied thereto from the sand boxes 9I,to the sand outlet pipes 92, the amount of sand thus supplied to saidoutlet pipes depending upon the amount or pressure of fluid supplied tothe sanders by way of the pipe 94.

The sanding valve device I9 is provided for controlling the supply offluid under pressure to the pipes 93 and 94 and comprises a casing 95having a chamber 99 containing a valve 91 which is arranged to controlcommunication between said chamber and a bore 99 to which pipe 94 isopen. The end of bore 98 opposite the valve 91 opens to a coaxial bore99 of greater diameter and which is open to the cleaning pipe 93. Avalve seat I09 is provided connecting the adjacent ends of bores 99 and99. The opposite end of bore 99 is open to a chamber I9I whichcontains-a piston I02 having at its outer face a .pressure chamber I03which is connected to a pipe I 94. Projecting from the opposite face ofpiston I92 through chamber HH and bores 99 and 99 into substantialengagement with valve 91 is an operating stem I95. This stem has a loosefit in the bore 99 for supporting same and is provided with a valve I99for engagement with the valve seat I99. Beyond this valve the portion ofstem I92 extending into the bore 98 is of smaller diameter than saidbore to permit the flow of fluid under pressure therethrough.

The operation of the sanding valve device is adapted to be controlled byeither the electromagnet valve device II or by the emergency valveportion 24 of the brake controlling valve device 2.

The electro-magnet valve device II comprises a magnet I91 having oneterminal connected to the ungrounded side of battery 81 through a wireI99 and the other terminal connected to a wire I99 which leads to onefinger of the manually operated switch I3 the other finger of which isgrounded. The electro-magnet valve device II further comprises a doublebeat valve IIO contained in a chamber I II which is connected to a sandreservoir I I2. The double beat valve H0 is provided for controllingcommunication between the chamber I II and a, chamber I I3 whichisconnected to the fluid pressure supply pipe I1,

and chamber III .and a chamber II4 which is connected to a pipe II5leading to one end of a double check valve device H9. A spring II1 isprovided in chamber M3 for urging the valve IIO to the position shown inthe drawing for opening communication between the fluid pressure supplypipe I1 and sand reservoir II2 when the electro-magnet I01 isdeenergized. When the electro-magnet I01 is energized it is adapted tomove the valve II 0 to a position opposite from that shown for closingcommunication between the supply pipe I1 and sand reservoir H2 and forconnecting said reservoir to the pipe H5 leading to the double checkvalve HE.

A pipe IIB connects the opposite end of the double check valve deviceIIB to the vent valve piston chamber 29. The side outlet of the doublecheck valve device H6 is connected to the pipe I04 leading to pistonchamber I93 of the sanding valve device I0. The double check valvedevice H6 is operative in the usual manner to close communicationbetween pipes H8 and 194 when fluid under pressure is supplied to pipeM5 for supply to pipe I04 and to close communication between pipes H5and I94 when fluid under pressure is supplied to pipe I91 for supply topipe I04.

The control valve device I2 comprises three flexible diaphragms I20, I2Iand I22 and three poppet valves I23, I24, and I25; the valve I29 beingarranged for control by diaphragm I29, the valve I24 by diaphragm I2Iand the valve M5 by the diaphragm I22. The diaphragm I29 has at one sidea chamber I29 connected to a fluid pressure supply pipe I21 and isoperative upon side of the diaphragm. A spring I39 is provided 1 forurging the valve I23 to its seat.

The diaphragm I2I has at one side a chamber I3I connected to a fluidpressure supply pipe I32 and is adapted to operate upon the supply offluid under pressure to said chamber to unseat the valve I24 for openingcommunication between passage I28 and a chamber I33 provided at theopposite side of said diaphragm. The diaphragm I22 has at one side apressure chamber I34 connected to a control pipe I39 and is adapted tooperate upon the supply of fluid under pressure to said chamber tounseat the valve I25 for opening communication between the fluidpressure supply passage I28 and a chamber I99 provided at the oppositeside of the diaphragm. A.

spring I31 is provided for urging the valve to its seated positionshown, while a spring I39 is provided by urging the valve I25 to itsseated position shown.

The supply passage I28 is connected to a fluid pressure supply reservoirI40 which is connected by way of a check valve MI and a hand operatedcut-out valve I42 to the brake pipe I5. It will be evident that when thebrake pipe :5 is charged with fluid under pressure in the usual manner,fluid will flow therefrom to the reservoir I40 and charge same tosubstantially the same pressure, and fluid at such pressure will besupplied to passage I28 in the valve device I2.

The diaphragm chambers I29, I33, and I35 is connected to chamber 96 inthe sanding valve' device I0.

Thecontrol pipes I21, I32, and |36 are connected to passages 62, 61, and56 leading to the medium, low and high speed magnet valve devices,respectively, in the differential relay valve device 3. By thisarrangement it will be noted that the chambers I26, |3|, and I34 areconnected in parallel with the chambers 43, 44, and 42, respectively, inthe relay valve device 3.

Operation of the brake equipment If it is desired to effect anapplication of the brakes on the vehicle, fluid under pressure issupplied to the brake application and release pipe 2| either bystraight-air operation of the brake valve device I or by automaticoperation of said brake valve device and the consequent operation of thebrake controlling valve device 2, as hereinbefore described. When arelatively low pressureis thus obtained in pipe 2| such pressure actingin chamber 82 on piston 8| of the switch device 5 actuates said pistonto move the contact into circuit closing relation with the contactfingers B6 forthereby connecting the battery 87 to wire leading to oneof each pair of fixed contact fingers in the speed governor device 4.

Letit be assumed that the vehicle is operating above the high speedlimit, in which case the movable governor contacts will occupy thepositions shown so that electric current supplied through wire 89 willbe thus supplied to the high speed magnet 53 and to the medium speedmagnet 59, for energizing said magnets. The low speed magnet 52 remainsdeenergized under this condition. The high and medium speed magnetvalves 54 and 60 are thus seated while the valves 55 and 6| areunseated.

Fluid under pressure supplied to the pipe 2| as above described thenflows directly to diaphragm chamber 45 and with the magnet controlledvalves .conditioned as just described, fluid under pressure will alsoflow from pipe 2| through passage 49 past the valve 55 to passage 56leading to diaphragm chamber 42 and also past the magnet valve 6| topassage 62 leading to diaphragm chamber 43. Fluid under pressure willalso flow from passage 48 past the low speed magnet valve 66 to passage61 leading to chamber 44. Under this speed condition the chambers 42 to45 will be thus all charged with fluid at the same pressure uponinitiating an application of brakes on the vehicle so that the threesmaller diaphragms 39, 49, and 4| will be in a balanced condition. Thepressure in chamber 42 acting on the largest diaphragm 38 is notbalanced however as just described and is therefore adapted to exert aforce acting in the direction of the left hand to control the operationof the application and release valve device 35 for supplying fluid underpressure to the brake cylinder device 8 to apply the brakes on thevehicle. The degree with which the brakes on the vehicle will be appliedas just described is controlled by the relatively large effective areaof diaphragm 3B and the degree of fluid pressure supplied to act inchamber 42. The pressure of fluid supplied to chamber 42 by operation ofeither the brake valve device or brake controlling valve device 2 may beof any degree desired to. provide for a chosen degree of braking on thevehicle and consequently a desired rate of deceleration thereof, as willbe apparent.

When, due to the brake application just described, the speed of thevehicle becomesreduced to below the high. speed limit the contact 12 inthe governor device 4 is moved out ofengagement with the fingers l5 andthereby effects deenergization of the high speed magnet 53 as a resultof which spring 51 seats valve 55 and un-, seats valve 54. The unseatingof valve 54 opens communication between diaphragm chamber 42 and theatmospheric release passage 58 thereby releasing the fluid underpressure from said chamber. This permits the pressure of fluid acting indiaphragm chamber 43 on the effective area of diaphragm 39 to controlthe operation of the application of the release valve device 35, andsince the effective area of the diaphragm 39 is less than that of thelarger diaphragm ,38, the force acting on the application and releasevalve device is likewise less and said device operates to effect acorresponding reduction in pressure in the brake cylinder 8 andin thedegree of brake application.

When the speed of the vehicle becomes reduced to below the medium speedlimit the contact 13 in the speed governor device is moved out ofengagement with the contact fingers l6 and thereby effectsdeenergization of the medium speed magnet 59. Spring 63 then acts toseat valve 6| and unseat valve 66, due to which, fluid under pressure isvented from the diaphragm chamber 43 through passage 62past valve 69 tothe release passage 58 and then to the atmos phere. As a result, thediaphragm 39 is rendered ineffective to further control the degree ofbrake application on the vehicle and the dia-' phragh 49 of smallerefiective area comes into control, and since this area is less than thatof diaphragm 39 the force controlling operation of the application andreleasevalve device ,35 is reduced a corresponding amount. Asa resultthe brake cylinder pressure is correspondingly reduced and the degree ofbrake application limited to the lower speed.

When the speed of the vehicle becomes reduced to the low speed limit,the speed governor device 4 moves the contact 14 into circuit closingrelation with the contactfingers 11 and thereby supplies electriccurrent from wire 89 to the low speed magnet 65 which is therebyenergized and operates to move the double beat valve 66 to its lowerseated position. In this vented to the atmosphere through passage 61 tothe release passage 58 so that the flexible diaphragm 40 is renderedineffective to further control the operation or the application'and therelease valve device 35, said control being passed on to the smallestdiaphragm 4|, and since the area of this diaphragm is less than that ofdiaphragm 49, the application and release valve device operates tocorrespondingly reduce the pressure of fluid in the brake cylinderdevice. This degree of brake application is then retained for allfurther reduction of vehicle speed since the governor contact I4 willremain in bridging re-,

of brake application. Instead, the diaphragm 39 i will be initiallyeffective under this condition and position of valve 66, diaphragmchamber 44 is l the diaphragms'fll and 4| will successively come intocontrol as the Vehicle speed is reduced to correspondingly reduce thedegree of the brake application in ,thesame manner as abovedescribed. Ifat the time the brake application is initiated the train is operating ata speed between the low and medium speed limits, the high and mediumspeed magnets will not be energized in which case neither of thediaphragms 38 or 39 will be efiective to control the degree of brakeapplication. Under this condition the diaphragm 40 will be initiallyeffective followed by the diaphragm M at the time the speed of thevehicle is reduced to below the low speed limit. In case the brakeapplication is initiated when the vehicle is operating below the lowspeed limit then, aswill be apparent, the diaphragms 38, 39, and 40 willnot come into action and diaphragm 41 will control the degree of brakeapplication.

It should be noted that all of the diaphragm chambers 42 to 45 aresupplied with fluid under pressure whenever the brakes on the vehicleare applied with the vehicle operating above the high speed limit. Whenthe brakes on the Vehicle are applied with the vehicle operating betweenthe high and medium speed limits. the diaphragm chamber 42 is vented,while the chambers 43 to 45 are all supplied with fluid under pressure.When the vehicle is operating at a speed between the medium and lowspeed limit both of the diaphragm chambers 42 and 43 are vented whilethe chambers 44 and 45 are supplied with fluid under pressure. Below thelow speed limit only chamber 45 is supplied with fluid under pressure,as will be apparent. Advantage is taken of this variable pressurecondition of chambers 42, 43 and 44 for controlling the operation of theimproved sanding mechanism to vary the supply of sand for sanding thetrack rails, as will now be described.

Operation of the sanding apparatus It will be noted that since diaphragmchambers I34, I26, and I3I in the fluid pressure supply control valvedevice I2 are connected to the diaphragm chambers 42, 43, and 44,respectively, in the relay valve device 3, as hereinbefore described,all of said diaphragm chambers in the control valve device I2 will besupplied with fluid under pressure Whenever the brakes on the vehicleare applied with the vehicle operating at or above the high speed limit.When the vehicle is operating between the high and medium speed limitsat the time the brakes thereon are applied and the diaphragm chamber 42in the diiierential relay device 3 is vented, the diaphragm chamber I34in the valve device I2 will likewise be vented. With the vehicleoperating between the medium and low speed limits at the time the brakesare applied and the chambers 42 and 43 in the differential relay valvedevice thus vented, the chambers I34 and I26 in the valve device I2 willalso be vented. When a vehicle is operating below the low speed limitall of the diaphragm chambers I34, I26, and I3I in the valve device I2will be vented along with the diaphragm chambers 42 to 44, respectively,in the valve I2.

When fluid under pressure is supplied to all of the diaphragm chambersI34, I26, and I3I in the valve device I2, such pressure acting on thediaphragms I22, I20, and I2I deflects said diaphragms in a downwardlydirection and unseats the valves I25, I23, and I24 which then supplyfluid under pressure from passage I28 to chambers I35, I29 and I33,respectively. The fluid under pressure thus supplied to chambers I35,

I29, and I33 then flows through thechokes I46,

then to pipe I48 leading to the sanding valve device I0. With thevehicle operating above the high speed limit the amount of fluid underpressure thus supplied to pipe I43 for sanding purposes, Which will bedescribed in greater detail hereinafter, is therefore governed by thecombined flow capacities of chokes I46, I44 and I45.

With the vehicle operating between the high and medium speed limits, inwhich case the diaphragm chamber I22 is vented as above described, thevalve I25 will be seated by spring I39, so that there can be no supplyof fluid under pressure for sanding through the choke I46 to the pipeI48. Under this speed condition it will thus be apparent that the supplyof fluid under pressure to pipe I46 for sanding is limited to thecombined flow capacities of chokes I44 and I45.

With the vehicle operating between the medium and low speed limits andboth diaphragm chambers I34 and I26 vented, both of the valves I25 andI23 will be seated. Under this condition the supply of air to pipe I48for sanding purposes is thus limited to the flow capacity of choke I45only.

When the vehicle is operating below the low speed limit all of thediaphragm chambers I34, I26, and I3I are vented along with diaphragmchambers 42 to 44 of the relay valve device and as a result all of thevalves I25, I23 and I24 in the valve device I2 will be seated so that nofluid pressure is supplied to pipe I48 for sanding.

It will now be apparent that whenever the brakes on the vehicle areapplied fluid under pressure will be supplied to the pipe I48 forsanding, which will presently be described, in an amount or at apressure which depends upon the number of chokes I46, I45 and I44 whichare rendered effective as governed by the speed at which the vehicle isoperating.

Whenever the brakes on the vehicle are applied with the vehicleoperating above the low speed limit the operator may effect sanding ofthe track rails by closing the switch I3 to effect energization of themagnet I 01. The energization of this magnet acts to shift the doublebeat valve H0 to the opposite position from that shown in the drawingand to thereby connect the sanding reservoir II2, which was previouslycharged with fluid under pressure from the supply pipe I'i, to pipe H5leading to one end of the double check valve device H6. The double checkvalve is thereby operated to close com munication between pipe H8 andpipe I04 and to connect the latter to pipe II5. Fluid pressure suppliedto pipe H5 then flows to pipe I04 and thence to piston chamber I03 inthe sanding valve device I0.

This supply of fluid under pressure to piston chamber I03 acts to movesaid piston and thereby the valve I06 in the direction of the left handto unseat the valve 01 to permit fluid under pressure supplied to thepipe I48 by the valve device I2 to flow past the valve 91 to the bore98. After the valve 9! is thus unseated the continued movement of pistonI02 moves the valve I06 into engagement with seat I00 to closecommunication between bore 98 and the bore 99. It will thus be apparentthat during this operation, the valve I06 will be unseated momentarilyafter valve 91 is unseated so that, for an instant, fluid under pressuresupplied from pipe I48 to bore 98 will be permitted to flow to the bore99 and then to the cleaning pipe 93 for supply to the rail sanders toclean same. This supply of fluid to the cleaning pipe 93 is however onlymomen-.

tary since the valve I06 is promptly moved into engagement with the seatI to out off such flow so that all further fluid supplied to the bore 98will flow through the sanding pipe 94 to the rail sanders 9 for blowingsand from said sanders to the outlet pipes 92- for supply to the trackrails for sanding same.

The amount of pressure of fluid supplied from 101 pipe I48 through thesand pipe 94 to the two rail. sanders 9 depends upon the number ofchokes I46, I45 and I44 in the valve device I2 which are effective tosupply fluid under pressure from the reservoir I40 to the pipe I48, andas 15 will be apparent from the above description, such 7 amount orpressure will vary according to the speed at which the vehicle isoperating. If the vehicle is operating above the high speed limit 3 the.supply of fluid under pressure for sanding 20 will be by way of thethree chokes so that the amount or pressure of fluid supplied to thesanders 9 for blowing sand to the sand pipes 92 will be relativelygreat. In case the vehicle is operating between the high and mediumspeed 25: limits and only the chokes I44 and I45 are effective to supplyfluid under pressure to pipe I48 to effect sanding, the amount orpressure of fluid will be less than when the vehicle is operating abovethe high speed limit, and the amount of 30 sand blown from the railsanders to the sand pipes 92 will also be correspondingly reduced- Asthe chokes I46, I45 and I44 are thus successively rendered ineffectiveupon reduction in the vehicle speed, the amount or pressure of fluid35.: supplied to the sanding valve device I0 for supply topipe 94 willbe reduced accordingly and the amount of sand blown through the sandpipes 92 will likewise be reduced in proportion. In other words, theamount of sand supplied to 0 the sand pipes 92 for sanding of the trackrails depends upon and will vary in proportion to the amount or pressureof fluid supplied to the pipe 94, and since such amount or pressure offluid depends upon the speed of the vehicle and is 45 varied inproportion to different ranges of speed, as above described, the trackrails will be sanded to substantially the most eflicient degree for allspeeds at which the vehicle may operate.

The fluid pressure supplied .from the sanding 50 reservoir II2 to pistonchamber I03 in the sandingvalve device I0 is gradually blown to theatmosphere through a choke I50 which may be provided in the pipe H5 andwhen this pressure is sufiiciently reduced a spring I5I acting on the 65sanding valve 91 urges said valve to its seat and thus returns the valveI06 and piston I02 to their normal positions shown and in whichthe'further supply of fluid under pressure from the pipe I40 to thesanding pipe 94 is cut ofl", thus terminat- 60 ing the sanding of thetrack rails. It will however be noted that the valve I06 is unseatedbefore the valve 91 obtains its seat, so that momentarily during theclosing movement of the valve 91 there will be a flow of fluid underpressure from bore 98 to the cleaning pipe 93. Thus at the terminationof the sanding period a sudden, but 1imited flow of fluid underpressure, is provided through the cleaning pipe 93 to clean out thesanders 9 so that they will be in condition to operate subsequently,when desired.

The length of time during which sanding can beeifected due to operationof the manually operated switch I3 is thus limited to the volume ofsanding'reservoir I I2 with respect to the venting capacity of chokeI50, but these parts are so designed as to insure sanding over asufiicient length of time to'bring a vehicle to substantially a stop. Atthe end of the sanding period the manually operative switch I3 may bereturned to its normal position. The magnet I0! is there- 5 bydeenergized permitting spring II'I to shift the double beat valve I I0back to the normal position shown and in which position the sandingreservoir II2 will be recharged with fluid under pressure from thesupply pipe I! so as to be in 10 condition for further manual sandingwhenever V such is desired.

Manual sanding of the track rails as above described may be effected atany time the brakes on the vehicle are applied, regardless of whetherthe application is due to straight air operation of the brake valvedevice I or to automatic service operation of the brake valve device andof the brake controlling valve device 2 as will be apparent.

However, when the brake valve device. I is operated to effect anemergency reduction in pressure in brake pipe I5 and the brakecontrolling valve device 2 responds to such reduction to effect anemergency application ofthe brakes on the vehicle, the sanding va'lvedevice i0 is operated automatically to effect sanding of the rails, aswill now be described.

When an emergency application of the brakes on the vehicle is effectedfluid under pressure supplied to the vent valve piston chamber 29 foractuating the vent valve piston 28 to unseat the vent valve 25 alsoflows from said chamber through pipe II8 to the double check valvedevice 0 wherein it acts to close communica- 3 tion between pipes H5 andI04 and to open communication between the latter and pipe IIB.

Fluid under pressure supplied to the pipe IIS then flows through pipeI04,,to the sanding valve device I0 and operates said device in the same40 manner ashereinbefore described to supply fluid under pressure frompipe I48 to the sanders 9 for effecting sanding of the track rails. Thefluid pressure thus provided for operating the vent valve piston 28 andsanding valve is not required, that is, until the vehicle is brought toa substantial stop. When the apparatus is operatedto supply sand forsanding during an emergency application of the brakes it will beapparent that the valve device I2 will operate in the same manner asheretofore described to vary the amount or the pressure of fluidsupplied for sanding according to the different speed ranges at whichthe vehicle operates to thereby insure most efficient braking but toprevent undue waste or loss of sand due to excessive use thereof. r

In. order that the supply of sand for sanding the track rails may bemaintained until the vehicle is brought to a substantial stop as abovedescribed, it will be apparent. that the contact 14 in the speedgovernor device 4 will not move into engagement with the fingers TI toeffect energization of the low speed magnet 65 and thus terminatesandinguntil the vehicle speed is reduced to alow' degree, such as forinstance from 753 three to five miles per hour which is sumciently lowto insure prompt completion of the stop without further sanding ofrails. This improved apparatus prevents the blowing of sand to the trackrails when the vehicle is stopped and thus avoids waste of sand undersuch a condition, as will be apparent.

The speed limits at which the high and medium speed governor contacts 12and 13 open the circuits controlled thereby may be whatever desired,such as for example sixty and thirtyfive miles per hour, respectively.

It will be apparent that sanding of the rails either during a straightair brake application or during an automatic service brake application,due to manual operation of the switch l3, may be terminated by releasingsaid switch or with the arrangement just described may be maintained byholding the switch I3 closed until the vehicle is brought nearly to astop.

With this improved sanding apparatus it will be noted that when astanding test of the brakes on a train is made, that is, a test with thetrain at rest before it leaves a terminal, no sand need be wasted, sinceneither the high nor medium speed magnets 53 and 59 will becomeenergized under such a condition.

The check valve MI is provided between the brake pipe and reservoir M0to prevent the backfiow of fluid under pressure from said reservoir tothe brake pipe whenever the brake pipe pressure is reduced below that insaid reservoir as in effecting an emergency application of the brakes.An adequate amount of fluid under pressure is thereby assured in thereservoir I40 for sanding purposes at all times and while any reductionin pressure in said reservoir will have some slight effect on the amountof fluid supplied through the valve device [2 to the sand pipe I48 forsanding, said reservoir will be sufficiently large to minimize thiseffect.

Summary From the above description it will now be noted that theimproved speed controlled sanding apparatus will provide sand forsanding purposes in amounts which are substantially proportional todifferent ranges in speed at which the vehicle will operate and whichwill thus provide substantially the same amount of sand on a certainunit length of track rail for all vehicle speeds. This arrangement willtherefore insure efficient braking of the vehicle but at the same timewill avoid undue use and waste of sand at the lower vehicle speeds; andprevent loss of sand when the vehicle is stopped.

It should be understood that the improved sanding apparatus isassociated with the speed controlled relay valve device 3 forillustrative purposes only. The improved apparatus may be arranged toprovide any desired number of different rates of said supplycorresponding to any desired number of different selected ranges ofspeed within the speed limits of the vehicle.

While one illustrative embodiment of the invention has been described indetail it is not the intention to limit the scope to that embodiment orotherwise than by the terms of the appended claims.

Having now described my invention, what I claim as new and desire tosecure by Letters Patent, is:

1. A sanding apparatus for sanding a rail under a railway vehicle,comprising, sander means for supplying sand for sanding, said rail,-regulating means for providing different rates of sand supply by saidsander means, means adjustable in accordance with one or another of aplurality of different selected ranges of vehicle speed within the speedlimits of the vehicle, mechanism conditionable substantially; inaccordance with the speed of the vehicle for controlling the adjustmentof the adjustable means, and control means operative upon the differentadjustments of the adjustable means for controlling said regulatingmeans to provide a rate of sand supply by said sander meanscorresponding to each difierent speed range adjustment of saidadjustable means.

2. A sanding apparatus for sanding a rail under a railway vehicle,comprising, sander means for supplying sand for sanding said rail,regulating means for providing different rates of sand supply by saidsander means, means adjustable successively during deceleration of thevehicle to a series of different conditions corresponding to differentselected ranges of speed of the vehicle, and means operative upon saidseries of successive adjustments to control said regulating means forproviding a corresponding series of successively reduced rates of sandsupply by said sander means, which rates are proportional to the speedrange adjustments of the adjustable means.

3. A sanding apparatus for sanding a rail under a railway vehicle,comprising, samr means from which sand for sanding said rail is adaptedto be blown by fluid under pressure at a rate proportional to the amountor pressure of said fluid, regulating means for varying the amount orpressure of fluid supplied to said sander means, and means adjustablesuccessively during deceleration of the vehicle to a series of differentconditions corresponding to different selected ranges of speed of thevehicle, said regulating means being controllable from the adjustablemeans and being operative upon each successive operation in said seriesof different conditions of said adjustable means to provide acorrespondingly reduced amount or pressure of fluid supplied to saidsander means.

4. A sanding apparatus for sanding a rail under a railway vehicle,comprising, sander means for supplying sand for sanding said rail,regulating means adjustable to provide one rate of sand supply by saidsander means for one speed range of the vehicle, another rate of sandsupply for another speed range of the vehicle and still another rate ofsand supply for a third speed range of the vehicle, means conditionablefor each of said different speed ranges to effect adjustment of saidregulating means to limit the rate of sand supply according to the speedrange, and means adjustable substantially in accordance with the speedof the vehicle for controlling the conditioning of said means.

5. A sanding apparatus for sanding a rail under a railway vehicle,comprising, sander means from which sand for sanding said rail isadapted to be blown by fluid under pressure at a rate proportional tothe capacity of a communication to supply fluid under pressure thereto,regulating means adjustable to vary the flow capacity of saidcommunication in proportion to different selected speed ranges of thevehicle within'the speed limits thereof, and means controllable by thespeed of the vehicle operative in each of said speed ranges to effectadjustment of said regulating means to provide the proper flow capacitythrough said communication for said speed range.

6. A sanding apparatus for sanding a rail under a railway vehicle,comprising, sander means from which sand for sanding said rail isadapted to be blown in a quantity which varies in accordance with theamount of fluid under pressure supplied thereto, regulating valve meansadjustable to supply different selected amounts of fluid .under pressureto said sander means corresponding to different selected speed ranges ofthe vehicle Within the speed limits thereof, and means controlled by thespeed of the vehicle and operative upon deceleration thereof to effectdifferent adjustments .of said regulating valve means to supply fluidunder pressure to said sander means in the selected amount for eachselected speed range.

'7. A sanding apparatus for sanding a rail under a railway vehicle,comprising, sander means for supplying sand for sanding said rail,regulating means adjustable to provide different rates of sand supply bysaid sander means corresponding to different selected speed ranges ofthe vehicle within the speed limits thereof, control means havingpositions corresponding in number to said speed ranges and operativeupon movement successively first to one and then to another of saidpositions to eflect a series of successive adjustments of saidregulating means to provide a corresponding number of different andsuccessively reduced rates of sand supply by said sander means, andmeans conditionable in accordance with the speed of the vehicle upondeceleration thereof to position said control means in first one andthen another of its positions corresponding to the speed range in whichthe vehicle is operating.

8. A sanding apparatus for sanding a rail under a railway vehicle,comprising, sander means for supplying sand for sanding-said rail,regulating means for controlling the rate of sand supply by said sandermeans and comprising a plurality of valves operable together to provideone rate of sand supply, said regulating means being operable to providea plurality of different rates of sand supply upon one or more of saidvalves being cut out of operation, and means for controlling saidregulating means and adjustable substantially in accordance with thespeed of the vehicle to render either all of said valves effective tocontrol the rate of sand supply or to cut one or more of said valves outof operation for thereby proportioning the rate of sand supplysubstantially to the speed of the vehicle within different speed rangesthereof.

9. A sanding apparatus for sanding a rail under a railway vehiclecomprising sander means for supplying sand for sanding said rail,regulating means for controlling the rate of sand supply by said sandermeans and comprising a plurality of valves operable together to providea chosen maximum rate ofsand supply, said regulating means beingoperable to provide a series of successively slower rates of sand supplyupon cutting first one and then another of said valves out of operation,and means conditionable in accordance with the speed of the vehicle forrendering all of said valves effective above a certainhigh speed limitof the vehicle and operative upon deceleration of the vehicle tosuccessively cut first one and then another of said valves out ofoperation at chosen reduced speeds of the vehicle.

10. A sanding apparatus for sanding a rail under a railway vehicle,comprising, sander means from which sand for sanding said rail isadapted to be blown by fluid under pressure at a rate dependent upon thepressure of said fluid, a plurality of valves for independentlysupplying fluid under pressure to said sander means for blowing sandtherefrom, the pressure of said fluid obtained at said sander meansvarying in proportion to the number of said valves which are operativeto supply fluid under pressure thereto, and means for controlling saidvalves and operable either to render all of said valves effective tosupply fluid under pressure to said sander means or to successivelyrender first one and then another of said valves ineffective to supplyfluid under pressure to said sander means.

11. A sanding apparatus for sanding a rail under a railway vehicle,comprising, sander means from which sand for sanding saidrail is adaptedto be blown by fluid under pressure at a rate dependent upon thepressure of said fluid, a plurality of valves for independentlysupplying fluid under pressure to said sander means for blowing sandtherefrom, the pressure of said fluid obtained at said sander meansvarying in proportion to the number of said valves which are operativeto supply fluid under pressure thereto, and means conditionable inaccordance with the speed of the vehicle for controlling said valves andoperable to render all of said valves operable at a certain high speedlimit of the vehicle and for rendering one of said valves inoperative ata certain lower speed, another of said valves inoperative at a stilllower speed, and for rendering still another of said valves inoperativeat a still lower speed of the vehicle.

12. A sanding apparatus for sanding a rail under a railway vehicle,comprising, sanding means operable to supply sand at various rates forsanding said rail, means having a plurality of chambers corresponding todifferent selected speed limits of the vehicle within the speed rangethereof, valve means operable upon a variation in fluid pressure in oneor more of said chambers for varying the rate of sand supply by saidsander means in proportion to the number of said chambers in which saidvariation in fluid pressure is effected, control means for effectingsaid variation of fluid pressure in one or more of said chambers, andmeans conditiona'ble substantially in accordance with the speed of thevehicle for selectively connecting one or more of said chambers to saidcontrol means for rendering said control means effective to effect avaria tion in fluid pressure therein.

13. A sanding apparatus for sanding a rail under a railway vehicle,comprising, sander means operable to supply sand at various rates forsanding said rail, means having a plurality of chambers corresponding todiiierent speed ranges of the vehicle within the speed limits thereofand to which chambers fluid under pressure is adapted to be supplied andreleased,

means operable when the pressure of fluid in substantially in accordancewith thespeed of the vehicle for controlling communication through whichfiuid under pressure is adapted to be supplied to and released from saidchambers and operative in accordance with different speed limits of thevehicle to condition said communication so as to vary the rate of sandsupply in proportion to the vehicle speed at said speed limits.

14. In combination, means having a plurality of chambers correspondingto different speed limits at which a vehicle is adapted to operatewithin its range of speed and being operable by fluid under pressureacting in one or another of said chambers to efiect various degrees ofbrake application on the vehicle according to which chamber isefiective, control means operative to provide fluid under pressure forsupply to said chambers for operating said means, means conditionablesubstantially in accordance with the speed of the vehicle forselectively connecting the chamber corresponding to the operating speedof the vehicle to said control means, and sanding means conditioned, inaccordance with which of said chambers is effective, to operate duringan application of the brakes on the vehicle to effect a supply of sandat a rate proportional to the respective speed limit.

15. In combination, means having a plurality of chambers correspondingin number to different selected speed limits Within the speed range ofthe vehicle and being operable upon the supply of fluid under pressureto all of said chambers to effect a maximum degree of brake applicationon the vehicle and upon subsequent venting of fluid under pressure firstfrom one and then another of said chambers to effect a reduction in thedegree of brake application for each chamber thus vented, means forsupplying fluid under pressure to all of said chambers, meansconditionable substantially in accordance with the speed of the vehicleand operative upon deceleration thereof during braking to effect at saiddifferent selected speed limits the venting of first one and thenanother of said chambers, sand control means operable to provide for asupply of sand at different rates for sanding a rail under the vehicle,and means operable upon the supply of fluid under pressure to all ofsaid chambers to effect operation of said sand control means to providefor a maximum rate of sand supply and upon the subsequent venting offirst one and then another of said chambers to effect adjustment of saidsand control means to provide for the supply of sand at a reduced ratewhich is in proportion to the reduced speed of the vehicle.

16. In combination, sander means from which sand for sanding a railunder a vehicle is adapted to be blown by fiuid under pressure at a ratedependent upon the pressure of said fluid, means operable by the forceof fluid under pressure to effect an application of the brakes on thevehicle, control means conditionable substantially in accordance withdifierent selected speeds of the vehicle for limiting said force to adegree which is proportional to the selected speed, and means operablein accordance with variations in the degree of said force to supplyfluid to said sander means at a pressure in proportion to the degree ofsaid force and thus in accordance with the selected speed of thevehicle.

17. In combination, sander means from which sand for sanding a railunder a vehicle is adapted to be blown by fluid under pressure at a ratewhich varies according to the pressure of fluid supplied to said sandermeans, valve means operable to supply fiuid under pressure to a chamber,means for controlling said valve means and conditionable in accordancewith the speed of the vehicle to efiect operation of said valve means tosupply fluid to said chamber at a rate which is dependent upon and inproportion to the speed of the vehicle, brake controlling meansoperative to efiect an application of the brakes on the vehicle, andmeans operable upon operation of said brake controlling means to opencommunication between said chamber and sander means through which fluidat the pressure supplied to said chamber is adapted to flow to saidsander means for blowing sand therefrom.

ELLIS E. HEWITT.

